Suicide and suicidal behaviour

doi:10.1016/S0140-6736(15)00234-2

The Lancet

Volume 387, Issue 10024, 19–25 March 2016, Pages 1227-1239

https://doi.org/10.1016/S0140-6736(15)00234-2 Get rights and content

Summary

Suicide is a complex public health problem of global importance. Suicidal behaviour differs between sexes, age groups, geographic regions, and sociopolitical settings, and variably associates with different risk factors, suggesting aetiological heterogeneity. Although there is no effective algorithm to predict suicide in clinical practice, improved recognition and understanding of clinical, psychological, sociological, and biological factors might help the detection of high-risk individuals and assist in treatment selection. Psychotherapeutic, pharmacological, or neuromodulatory treatments of mental disorders can often prevent suicidal behaviour; additionally, regular follow-up of people who attempt suicide by mental health services is key to prevent future suicidal behaviour.

Introduction

Suicide takes a staggering toll on global public health, with almost 1 million people dying from suicide worldwide each year.¹ WHO has declared that reducing suicide-related mortality is a global imperative, a welcome contrast to the traditional taboo that has surrounded suicidal behaviours. Cultural and moral beliefs about suicide, and unnecessarily pessimistic views about treatment and prevention of suicide, are barriers to patient self-disclosure and clinicians' routine inquiries about suicidal thoughts. About 45% of people who die by suicide consult a primary care physician within 1 month of death, yet documentation of physician inquiry or patient disclosure is rare.² We review the epidemiology, risk factors, and effective interventions in primary care and specialty mental health facilities aimed at the prevention or treatment of suicidal behaviour.

Section snippets

Definitions and assessment

Clear discussion, accurate research, and efficient treatment require accepted definitions of suicidal behaviours. The difficulty of establishing intent of self-harming behaviours has hindered efforts to streamline the historically heterogeneous suicide nomenclature, but efforts, such as those resulting in the Columbia Classification Algorithm of Suicide Assessment,³ have contributed to standardising nomenclature (table). The severity of suicidal behaviour varies, on the basis of family studies

Epidemiology

Precise global estimates of suicide rates are difficult to obtain, as only 35% of WHO member states have comprehensive vital registration with at least 5 years of data.¹ Globally, an estimated 11·4 suicides per 100 000 people occur per year, resulting in 804 000 deaths.¹ Suicide rates vary within and between countries, with as much as a ten-times difference between regions; this variation is partly correlated with economic status and cultural differences.¹ Cultural influences might trump

Contemporary models of suicide risk

In the past century, the contributions of both social and individual factors to understanding suicide risk have been recognised. Several models have been proposed, most emphasising the interaction between predisposing and precipitating factors.17, 18, 19, 20 Figure 2 shows putative temporal relationships between different suicide risk factors. Suicide has many causes, with substantial variability in the strengths and patterns of association of risk factors across sex, age, culture, geographic

Population-level risk factors

More than a century ago, Durkheim recognised the effect of population-level social factors on suicide rates. Increases in suicide rates among indigenous peoples, such as Canadian Inuits, correlate with social changes such as forced settlement, assimilation, and disruption of traditional social structure.⁶ Conversely, suicide is rare in homogeneous societies with high social cohesion, common values, and moral objections to suicide,23, 24 although the latter might also lead to under-reporting.

Prevention

Several reviews of the efficacy of different prevention practices have been published.100, 101, 102, 103 School, workplace, and community-based interventions, and multicomponent primary care interventions, can reduce the incidence of suicide or suicidal behaviour, as can the organisation of and access to care, and reduced access to means of suicide.

School-based interventions reduce the incidence of suicide ideation or suicidal behaviour. The Good Behaviour Game, a teacher-led classroom

Perspectives

Suicidal behaviours are heterogeneous, both in terms of presentation and treatment, making it difficult to provide an all-encompassing model of suicide risk or to suggest a clear treatment formula. Because of the complexity and the breadth of the subject, we present an overview of the present state of knowledge in suicide research. Certain aspects, such as detailed discussions of the psychology of suicide and suicide prevention, have been well described elsewhere.17, 141 Ongoing advances in

Search strategy and selection criteria

The previous Lancet Seminar on suicide was published in 2009. We searched PubMed and the Cochrane Library from Jan 1, 2009, to May 30, 2015, with the terms suicide, suicidal behaviour, and self-harm along with category-specific terms, including epidemiology, genetics, intervention, prevention, and psychotherapy. Titles and abstracts of search results were read and sorted to assess inclusion of the article. We identified further articles by scanning the reference sections of selected

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Cited by (1250)

Hospitalizations and emergency department visits for self-harm in Canada during the first two years of the COVID-19 pandemic: A time series analysis
2024, Journal of Affective Disorders
Rates of hospitalizations and emergency department (ED) visits due to self-harm are important indicators for understanding the impact of the COVID-19 pandemic on mental health. The objective of this study was to assess changes in self-harm hospitalizations and ED visits in Canada during the first two years of the pandemic.
Rates of self-harm hospitalizations and ED visits during the pandemic were predicted based on regression analyses that modeled trends over a 5-year pre-pandemic period from fiscal year 2015 to 2019. The ratios of observed and model predicted (expected) rates in 2020 and 2021 were estimated separately to assess changes during the pandemic.
Overall, rates of self-harm hospitalizations and ED visits were lower than expected during the pandemic, especially in 2020. In 2021, rates for females returned to near-expected levels; but they remained lower than expected for males. Females aged 10–14 years had higher than expected rates. The rate ratio of observed rate over expected rate was 1.2 in 2020 but further increased to 1.8 in 2021 for both hospitalizations and ED visits. Higher than expected rates were also observed among females aged 15–19 years in 2021 only.
Suicide attempts and non-suicidal self-harm cases could not be distinguished.
We observed lower than or close to expected rates of self-harm hospitalizations and ED visits during the pandemic for most population groups. The increased rates for young females highlights the importance of continued surveillance post-pandemic and targeted mental health services and suicide prevention programs.
Divorce, genetic risk, and suicidal thoughts and behaviors in a sample with recurrent major depressive disorder
2024, Journal of Affective Disorders
Theories of risk for suicidal thoughts and behaviors (STB) implicate both interpersonal and biological factors. Divorce/separation and aggregate genetic liability are robustly associated with STB, but have seldom been evaluated in conjunction with one another. Furthermore, whether these factors are effective predictors in high-risk populations is not clear.
Analyses were conducted in a sample of Han Chinese women with severe recurrent major depressive disorder (maximum N = 4380). Logistic regressions were used to evaluate the associations between divorce/separation and polygenic scores (PGS) for suicidal ideation or behavior with STB. Where appropriate, additive interactions between divorce and PGS were tested.
Divorce/separation was significantly associated with increased risk of suicidal ideation, plans, and attempts (odds ratios = 1.28–1.61). PGS for suicidal ideation were not associated with STB, while PGS for suicidal behavior were associated with ideation and plans (odds ratios = 1.08–1.09). There were no significant interactions between divorce/separation and PGS.
Consistent with theories of suicidality, the disruption or end of an important interpersonal relationship is an indicator of risk for STB. Aggregate genetic liability for suicidal behavior more modestly contributes to risk, but does not exacerbate the negative impact of divorce. Thus, even within a high-risk sample, interpersonal and biological exposures distinguish between those who do and do not experience STB, and could motivate targeted screening. Further research is necessary to evaluate whether and how the context of divorce contributes to variation in its effect on STB risk.
Suicide risk after discharge from in-patient psychiatric care: A 15-year retrospective cohort study of individual patient data
2024, Journal of Affective Disorders
Suicide rates are known to be increased in patients after discharge from in-patient psychiatric treatment. However, evidence on risk factors for suicide within this patient group are contradictory. Thus, this study aims to investigate suicide after discharge from a sizeable psychiatric care facility to determine associated risk factors.
Data on individual patient level from a 15-year single-centre cohort were linked to data from the national death registry and cumulative incidence rates were calculated applying competing risk models. Independent variables included the patients' sex, age at admission, diagnosis, and length of admission. For each of these factors, subdistribution hazards ratios were calculated using a Fine-Gray model.
In our sample of 18,425 discharges, when using patients with the diagnosis of substance-use-disorders as a comparator, a significant increase in hazard of post-discharge suicide for male sex (SHR = 1.67;p = 0.037) as well as the discharge diagnoses of affective disorders (SHR = 3.56;p = 0.017) and neurotic stress and somatoform disorders (SHR = 3.73;p = 0.024) were found. Interestingly, the hazard of suicide significantly decreased in more recent discharges (SHR = 0.93;p = 0.006). No statistically significant association of the length of admission with the suicide risk was found (SHR = 0.98;p = 0.834).
Limitations.
Suicides may have been mis-identified as natural death in the national death register.
Male sex and distinct diagnoses were associated with an increased risk for suicide after discharge from a psychiatric care institution. The markedly increased suicide risk within this patient collective highlights the need for the development of tools to assess suicidal behaviour in this group of patients reliably.
The role of interpersonal stressors and connectedness in acute suicide risk and the suicide crisis syndrome during the COVID-19 pandemic
2024, Journal of Affective Disorders
The global COVID-19 pandemic rapidly and drastically impacted everyday life and relationships. Fear of contracting and spreading the virus brought governments and individuals to adopt strict social distancing measures. These changes have had a significant negative impact on mental health, including a suggested increase in suicidal behaviors. The present study examined the role of interpersonal stress and connectedness in suicidal ideation, deliberate self-harm, suicide attempts, and the suicide crisis syndrome during the COVID-19 pandemic.
An international sample of 7837 adult participants was recruited across ten participating countries to complete an anonymous online battery of self-report questionnaires. Questionnaires assessed suicide-related outcomes, stressful life events (SLE), and connectedness. Multilevel regression analyses were used to examine the associations between SLE and connectedness on suicide-related outcomes within the past month.
Interpersonal SLEs and low connectedness were associated with an increased likelihood of suicide-related outcomes and increased severity of suicide crisis syndrome. Specifically, higher rates of SLEs and lower levels of connectedness were associated with more suicide-related outcomes.
The use of a cross-sectional design and snowball sampling method may restrict the ability to establish causal relationships and limit the representativeness of the findings.
Our findings suggest elevated suicide-related outcomes during the COVID-19 pandemic among individuals experiencing multiple interpersonal stressful life events and low connectedness with others. The circumstances of social life during the COVID-19 pandemic highlight the urgency of implementing preventive programs aimed at mitigating potential suicide risks that may arise in the aftermath of public stress situations.
Suicidal thoughts and behaviors in the Kingdom of Saudi Arabia
2024, Journal of Affective Disorders
Suicidal thoughts and behaviors (STB) constitute an escalating public health concern globally. Despite the growing burden of suicidal ideation, plan, and attempts, national information on the trends of STB is lacking in the Kingdom of Saudi Arabia (KSA). Therefore, we aim to report on the prevalence, correlates, and treatment-seeking behaviors associated with STB in the country using nationally representative information from The Saudi National Mental Health Survey (SNMHS).
The SNMHS is a national household survey of Saudi citizens aged 15–65 (n = 4004). The adapted Composite International Diagnostic Interview (CIDI) 3.0 was administered to produce lifetime and 12-month prevalence and treatment estimates of STB in the KSA. Associated correlates were calculated using cross tabulations and logistic regressions.
Suicidal ideation, plan, and attempt had respective lifetime prevalence rates of 4.90 %, 1.78 %, and 1.46 %; 12-month prevalence rates of 1.82 %, 0.89 %, and 0.63 %. Significant correlates of STB include younger age, female gender, low education, urban rearing, and singe marital status. STB were also significantly associated with the presence of prior mental disorders, childhood adversities, and low treatment-seeking.
High unmet need and significant sociocultural and psychological risk factors have been identified in association with STB in the KSA. Given the community-based nature of the SNMHS and the limited national data on STB in the Middle East and North Africa region, our findings can extend to inform the necessary healthcare policies, treatment plans, and prevention strategies needed to alleviate the burdens of STB in the region.
Mediating effect of inflammation on the relationship between sleep disruption and suicidal ideation in major depressive disorder
2024, Journal of Affective Disorders
Sleep disruption, particularly insomnia, is a notable characteristic of depression and is associated with an increased risk of suicide in patients diagnosed with major depressive disorder (MDD). Moreover, the pathophysiology of depression and suicide has been linked to inflammation, specifically proinflammatory cytokines. However, the complex interplay among these factors in individuals with MDD remains poorly understood. This study investigated the mediating role of inflammatory cytokines in the relationship between sleep disruption and suicidal ideation (SI), with a particular emphasis on gender differences.
This study used a cross-sectional design in which 281 individuals diagnosed with MDD were recruited from psychiatric clinics. The main assessments included the evaluation of sleep disruption, inflammatory markers, and SI. The Beck Scale for Suicide Ideation (SSI) scores was employed to quantify SI, whereas HAMD-SLD, a component of the Hamilton Rating Scale (HAMD-17), was used to evaluate sleep disruption. Blood analysis was performed to measure inflammatory markers.
For females diagnosed with MDD, significant associations between sleep disruption and the levels of IL-6 (B = 0.994, p = 0.013) and TNF-α (B = 1.986, p = 0.016) were found when IL-6 or TNF-α were considered as mediators in the regression model. In addition, IL-6 (B = 5.689, p < 0.001) and TNF-α (B = 9.916, p = 0.006) exhibited strong correlation with SSI scores.
The primary results of this study indicate that IL-6 and TNF-α could function as potential mediators in the relationship between sleep disruption and SI among female patients diagnosed with MDD.
Name of the registry: Zhejiang University
Trial registration number: ChiCTR1800017626
Date of registration: 2018-08-07, 'Retrospectively registered'
URL of trial registry record: https://www.chictr.org.cn/showproj.html?proj=27321

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View full text

SeminarSuicide and suicidal behaviour

Summary

Introduction

Section snippets

Definitions and assessment

Epidemiology

Contemporary models of suicide risk

Population-level risk factors

Prevention

Perspectives

Search strategy and selection criteria

Lancet

Psychiatr Clin North Am

Lancet Psychiatry

Ann Epidemiol

Trends Neurosci

Psychiatr Clin North Am

Biol Psychiatry

Trends Parasitol

J Affect Disord

Psychoneuroendocrinology

J Affect Disord

Lancet

J Affect Disord

Lancet

Prog Brain Res

Adv Genet

Pharmacol Res

Biol Psychiatry

Lancet Psychiatry

Biol Psychiatry

Biol Psychiatry

Lancet

Prog Neuropsychopharmacol Biol Psychiatry

Mental health: suicide prevention

Health care contacts in the year before suicide death

J Gen Intern Med

Columbia Classification Algorithm of Suicide Assessment (C-CASA): classification of suicidal events in the FDA's pediatric suicidal risk analysis of antidepressants

Am J Psychiatry

Suicidal behavior runs in families. A controlled family study of adolescent suicide victims

Arch Gen Psychiatry

Suicide among immigrants in Europe—a systematic literature review

Eur J Public Health

Prevalence, correlates, and treatment of lifetime suicidal behavior among adolescents: results from the National Comorbidity Survey Replication Adolescent Supplement

JAMA Psychiatry

Twelve-month prevalence of and risk factors for suicide attempts in the World Health Organization World Mental Health Surveys

J Clin Psychiatry

Cross-national prevalence and risk factors for suicidal ideation, plans and attempts

Br J Psychiatry

Prevalence of suicide ideation and suicide attempts in nine countries

Psychol Med

Suicidal thoughts and behaviours among Australian adults: findings from the 2007 National Survey of Mental Health and Wellbeing

Aust N Z J Psychiatry

Lifetime prevalence and correlates of suicidal ideation, plan, and single and multiple attempts in a Korean nationwide study

J Nerv Ment Dis

Hospital presenting self-harm and risk of fatal and non-fatal repetition: systematic review and meta-analysis

PLoS One

Natural history of suicidal behaviors in a population-based sample of young adults

Psychol Med

Suicide and seasonality

Acta Psychiatr Scand

Neurobiology of suicidal behaviour

Nat Rev Neurosci

The interpersonal theory of suicide

Psychol Rev

The molecular bases of the suicidal brain

Nat Rev Neurosci

Suicide and family loading for affective disorders

JAMA

A pocket of very high suicide rates in a non-violent, egalitarian and cooperative population of South-East Asia

Psychol Med

Relationship of suicide rates to economic variables in Europe: 2000–2011

Br J Psychiatry

Economic suicides in the Great Recession in Europe and North America

Br J Psychiatry

Media influences on suicide and attempted suicide

Suicide and the media

Ann N Y Acad Sci

Familial aggregation of suicidal behavior: a family study of male suicide completers from the general population

Am J Psychiatry

Seminar
Suicide and suicidal behaviour